Method for operating an internal combustion engine

Abstract

A method for operating an engine includes, but is not limited to acquiring a value of at least one engine operating parameter, using the set of values for determining a predicted value of a combustion parameter indicative of fuel combustion performance within an cylinder, using the values as input of a data-set returning as output a correlated correction value of the combustion parameter, using the correction value and the predicted value for determining an expected value of the combustion parameter, feed-forward controlling an injection of fuel into the engine cylinder targeting the expected value of the combustion parameter, measuring a value of the combustion parameter within the cylinder due to that injection of fuel, using a difference between the expected value and the measured value of the combustion parameter for correcting the correction value of the data-set that is correlated to the set of engine operating parameter values.

1 . A method for operating an internal combustion engine, comprising:
 acquiring a set of values for a plurality of engine operating parameters;   determining a predicted value of a combustion parameter that is indicative of a fuel combustion performance within a cylinder of the internal combustion engine using the set of values;   using the set of values as input of a data-set returning as an output of a correlated correction value of the combustion parameter;   determining an expected value of the combustion parameter using the correction value;   feed-forward controlling an injection of fuel into the cylinder targeting the expected value of the combustion parameter;   measuring a value of the combustion parameter within the cylinder due to the injection of fuel; and   correcting the correction value of the data-set that is correlated to the set of values for the plurality of engine operating parameters using a difference between the expected value and the measured value of the combustion parameter.   
     
     
         2 . The method according to  claim 1 , wherein the determining the expected value of the combustion parameter comprises adding the correction value to the predicted value of the combustion parameter. 
     
     
         3 . The method according to  claim 2 , wherein the determining the correction value comprises adding the difference between the expected value and the measured value of the combustion parameter. 
     
     
         4 . The method according to  claim 1 , wherein the determining the predicted value of the combustion parameter comprises
 receiving as input the set of engine operating parameter values; and   returning as output the predicted value of the combustion parameter.   
     
     
         5 . The method according to  claim 1 , wherein at least one engine operating parameter of the plurality of engine operating parameters is engine speed. 
     
     
         6 . The method according to  claim 1 , wherein at least one engine operating parameter of the plurality of engine operating parameters is a quantity of injected fuel. 
     
     
         7 . The method according to  claim 1 , wherein the determining the predicted value of the combustion parameter comprises using a value of an additional engine operating parameter of the plurality of engine operating parameters. 
     
     
         8 . The method according to  claim 7 , wherein these additional engine operating parameters is a start of injection of a main injection pulse. 
     
     
         9 . The method according to  claim 7 , wherein these additional engine operating parameters is a value of an intake pressure. 
     
     
         10 . The method according to  claim 7 , wherein these additional engine operating parameters is a value of an intake temperature. 
     
     
         11 . The method according to  claim 7 , wherein these additional engine operating parameters is a value of an energizing time of the main injection pulse. 
     
     
         12 . A method according to  claim 1 , wherein the combustion parameter is a crank angle at which a given fraction of the injected fuel has burnt. 
     
     
         13 . A method according to  claim 1 , wherein the injection of fuel is feed-forward control comprising:
 setting a desired value of the combustion parameter,   determining a value of the start of injection corresponding to the desired value of the combustion parameter using a polynomial relationship between the combustion parameter and the start of the injection using the expected value of the combustion parameter and a corresponding value of a start of injection; and   starting the fuel injection at the value of the start of injection.   
     
     
         14 . A method according to  claim 13 , wherein the value of the start of injection is corrected using a feed-back control seeking to minimize an error between the desired value and the measured value of the combustion parameter. 
     
     
         15 . A computer readable medium embodying a computer program product, said computer program product comprising:
 an operating program for operating an internal combustion engine, the operating program configured to:   acquire a set of values for a plurality of engine operating parameters;   determine a predicted value of a combustion parameter that is indicative of a fuel combustion performance within a cylinder of the internal combustion engine using the set of values;   use the set of values as input of a data-set returning as an output of a correlated correction value of the combustion parameter;   determine an expected value of the combustion parameter using the correction value;   feed-forward control an injection of fuel into the cylinder targeting the expected value of the combustion parameter;   measure a value of the combustion parameter within the cylinder due to the injection of fuel; and   correct the correction value of the data-set that is correlated to the set of values for the plurality of engine operating parameters using a difference between the expected value and the measured value of the combustion parameter.   
     
     
         16 . The computer readable medium embodying the computer program product according to  claim 15 , wherein operating program is configured to determine the expected value of the combustion parameter by adding the correction value to the predicted value of the combustion parameter. 
     
     
         17 . The computer readable medium embodying the computer program product according to  claim 15 , wherein the operating program is configured to determine the correction value by adding the difference between the expected value and the measured value of the combustion parameter. 
     
     
         18 . The computer readable medium embodying the computer program product according to  claim 15 , wherein the operating program is configured to:
 receive as input the set of engine operating parameter values; and   return as output the predicted value of the combustion parameter.   
     
     
         19 . The computer readable medium embodying the computer program product according to  claim 15 , wherein at least one engine operating parameter of the plurality of engine operating parameters is engine speed. 
     
     
         20 . The computer readable medium embodying the computer program product according to  claim 15 , wherein at least one engine operating parameter of the plurality of engine operating parameters is a quantity of injected fuel.